VHF Band Frequency

There are two band frequency:

1. VHF Low-Band
This band is located at 25 MHz to 50 MHz and generally uses channels 20 kHz wide. Communications ranges can be the greatest in this band; however, the radio signals do
not reflect effectively off hills, buildings, and other surfaces, so there may be dead spots within the general area of coverage of a base station. These frequencies, especially at the lower end of the band, are subject to ionospheric “skip,” which can carry a signal very long distances (and cause interference to other users). This band also has the highest level of ambient noise, which reduces the performance of receivers
operating in this band compared to other, higher frequency-bands.

2. VHF High-Band
This band is located at 150 MHz to 174 MHz and uses channels 25 kHz or
30 kHz wide. Adjacent channels may be separated by 12.5 kHz to 15 kHz for
geographically separated systems. Radio signals in this band have a shorter
propagation range, experience less noise than those in the VHF low-band, and are not
subject to ionospheric “skip.” Diffraction over hills and around other obstacles reduces dead areas of coverage.